unplug computers when you hear thunder?

[yakko]

I have UPS units on my machines.

 

[tcsenter]

I've replaced (tech support) 50 or 60 modems due to power surge over the phone line but only one or two PS's due to the idiot luser bypassing the UPS for some unknown reason....

90% of the time this was caused by a surge suppressor. Damaging surges rarely if ever ENTER on a phone line, they enter through a power line and EXIT through the phone lines, since phone company service drops are typically grounded far better than your home's AC service. This is why phone service rarely ever goes down, the entire system is well grounded. Most homes have poor earth grounds, a surge suppressor is ONLY as good as earth ground and the shortest path to it, unless your surge suppressor has some serious arrestance features (those start at a couple hundred dollars).

A surge supressor is only one component of effective surge protection. Short paths to a good earth ground are the other. Most homes do not qualify simply because most homes are built to satisfy codes based on NEC (National Electric Code), which considers surge protection and protecting appliances as an afterthought. The primary goal of NEC is to offer current a more attractive potential than your body, but this is still far higher than electronics can withstand.

UPS don't cut it, APC's written UPS protection guarantee expressely does not cover against common mode surges, only normal (differential) mode surges. Problem is, the vast majority of damaging surges are common mode. Those who think that APC or Tripp-lite are going to actually honor that $25,000 guarantee have never read the written protection coverage policy (fine print).

 

[ndee]

Only if you're a wussy.